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		<p>
            <br />
            <i>Empty points </i>are data points that do not have Y values or have been marked 
            as empty. They are visually displayed in the chart area. Empty points are not 
            the same as missing data points, which&nbsp; refer to data points that are missing in 
            a data set.</p>
		<p>The following example shows that there is no data for Wednesday. </p>
		<p>
			<TABLE id="Table1" cellSpacing="1" cellpadding="1" width="500" border="0">
				<tr>
					<td><IMG alt="Missing Data?" src="MissingPoints1.PNG" border="0"><BR>
						</td>
					<TD valign="top">&nbsp;
						<BR>
						<TABLE id="Table2" cellSpacing="1" cellpadding="1" width="100%" border="1">
							<tr>
								<TD valign="center" align="middle"><STRONG>X</STRONG></td>
								<TD valign="center" align="middle"><STRONG>Y</STRONG></td>
							</tr>
							<tr>
								<td>Monday</td>
								<td>978</td>
							</tr>
							<tr>
								<td>Tuesday</td>
								<td>345</td>
							</tr>
							<tr>
								<td>Thursday</td>
								<td>567</td>
							</tr>
							<tr>
								<TD height="21">Friday</td>
								<TD height="21">778</td>
							</tr>
							<tr>
								<td>Saturday</td>
								<td>46</td>
							</tr>
							<tr>
								<td>Sunday</td>
								<td>78</td>
							</tr>
						</TABLE>
					</td>
				</tr>
			</TABLE>
		</p>
		<p>If the X values of the plotted series are indexed, then it is possible that the 
            missing data is can be overlooked by the chart reader (see the figure below).</p>
		<p><IMG alt="Missing Data and Indexed Points" src="MissingPoints2.PNG" border="0"><BR>
			</p>
		<p>In this case, use an empty point to clarify that a data point is missing. For 
            example:</p>
		<p><IMG alt="Missing Data and Indexed Points" src="MissingPoints3.PNG" border="0"></p>
		<H3>Empty Points Usage</H3>
		<p>Use empty points to:</p>
		<UL>
			<LI>
			    Represent points with NULL values.
			<LI>
			Change the appearance of missing data points.
			<LI>
				Align two or more series.
			</LI>
		</UL>
		<p>Empty data points can be added to a series using:
		</p>
		<UL>
			<LI>
				The Empty 
			property of each data point in a series. If Empty is set to <b>True</b>, a point is marked as empty.
			<LI>
				Data binding to DBNull values.&nbsp;If a point is data bound to a DBNull value 
				it will be marked as empty.<LI>
				The InsertEmptyPoints method of the DataManipulator class, 
				which checks for missing data and inserts empty points into 
				a series using intervals.</LI></UL>
		<H3>Empty Points Styles</H3>
		<p>Empty points can be displayed as a marker or a line that connect the nearest two 
            points. It can be displayed as an average of the adjacent points or as having a 
            value of zero (see the figure below).</p>
		<p><IMG src="MissingPoints.png" border="0"><BR>
			</p>
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